Defence chiefs are drawing up plans for big cuts in Britain's military equipment programme, abandoning, cutting, or delaying projects as a result of severe pressures on their budget. They are facing up to the fact that they have been signing up to prestigious, programmes - including the procurement, at a cost of £3.9bn, of two aircraft carriers, the largest ships ever to be built for the Royal Navy - without considering how they were going to be funded, senior officials say.

"They ordered and ordered without paying attention to the budget," one senior defence source admits.

Ministers insist there is no need for a full-scale defence review despite a desperate, unanticipated, shortage of equipment - notably tough armoured personnel carriers and helicopters - for British troops in Afghanistan engaged in operations for which there is no end in sight. Ministers refer, instead, to "an examination of the equipment programme".

Faced with an estimated £2bn hole in the defence budget, military planners are preparing to tell ministers that the time has come to make hard decisions. Officials say these are likely to include:

· Abandoning a £1bn plan to buy 70 Super Lynx helicopters for the army and navy, a move with serious implications for Yeovil, home of AgustaWestland which would have manufactured the aircraft;

· Cutting the number of new Type 45 destroyers for the navy from the original 12 planned to six;

· Scrapping early a number of the navy's older destroyers and frigates;

· Reducing the number of Future Rapid Effects System (Fres) hi-tech armoured vehicles planned for the army;

· Scrapping some of the army's large tanks and long-range howitzers;

· Offloading more Eurofighter/Typhoon aircraft to the Saudis who have already bought 72 of them.

Defence officials suggest that money could be saved by buying alternatives to the Future Lynx, such as American Black Hawk helicopters, off the shelf. However such a move could lead AgustaWestland, the Italian-owned company, to close its plant in Yeovil with a loss of 4,000 jobs.

Military commentators say the controversy has echoes of the Westland affair of the mid-1980s when Michael Heseltine resigned as defence secretary. He quit in protest at the decision to allow a US firm to take over the helicopter company rather than a European consortium.

The Lynx is not the only helicopter to be abandoned. The army's fleet of Gazelle helicopters is to be phased out early. The only army regiment assigned to cope with civil emergencies, including floods, is to be disbanded next year.

Over the past year Gazelles have flown more hours than other military helicopters, according to MoD figures. Ministers argue that Gazelles do not play a significant "combat" role and that the Lynx would also be unsuitable for operations in Afghanistan. British troops there need bigger helicopters, such as Chinooks, officials say.

Nick Harvey, Liberal Democrat defence spokesman, said: "Disbanding the country's only army air regiment specifically trained to deal with domestic security seems to run wholly counter to the prime minister's recent national security strategy. Given how overstretched our forces are in other parts of the world, there is a danger that we leave the home front unprepared."